Fluid delivery device with variable force spring

ABSTRACT

A compact fluid dispenser for use in controllably dispensing fluid medicaments such as antibiotics, blood clotting agents, analgesics, and like medicinal agents from collapsible containers at a uniform rate. The dispenser includes a novel stored energy source that is provided in the form of a compressible-expandable member that functions to continuously and uniformly expel fluid from the apparatus reservoir. The apparatus further includes a novel fluid flow control assembly that precisely controls the flow of the medicament solutions from the apparatus reservoir to the patient.

This is a Divisional application of U.S. application Ser. No. 11/982,644filed Oct. 31, 2007 now U.S. Pat. No. 7,828,770.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC

Not Applicable

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to fluid dispensing apparatus.More particularly, the invention concerns a medicament delivery devicefor dispensing medicinal fluids to ambulatory patients that includes anovel stored energy source in the form of a variable force spring. Thevariable force spring is cooperatively associated with the collapsiblereservoir of the device and functions to deliver a variable force to thereservoir that tends to urge fluid flow therefrom at a substantiallyconstant rate. In the preferred form of the invention the stored energysource uniquely comprises an elongated, pre-stressed strip of springmaterial that is formed into coils and exhibits a cross-sectional massthat varies along its length.

2. Description of Related Art Including Information Disclosed Under 37CFR 1.97 and 1.98

A number of different types of medicament dispensers for dispensingmedicaments to ambulatory patients have been suggested in the past. Manyof the devices or apparatus seek either to improve or to replace thetraditional gravity flow and hypodermic syringe methods which have beenthe standard for delivery of liquid medicaments for many years.

The prior art gravity flow methods typically involve the use ofintravenous administration sets and the familiar flexible solution bagsuspended above the patient. Such gravametric methods are cumbersome,imprecise and require bed confinement of the patient. Periodicmonitoring of the apparatus by the nurse or doctor is required to detectmalfunctions of the infusion apparatus. Accordingly, the prior artdevices or apparatus are not well suited for use in those instanceswhere the patient must be transported to a remote facility fortreatment.

With regard to the prior art, one of the most versatile and unique fluiddelivery apparatus developed in recent years is that developed by one ofthe present inventors and described in U.S. Pat. No. 5,205,820. Thecomponents of this novel fluid delivery apparatus generally include: abase assembly, an elastomeric membrane serving as a stored energy means,fluid flow channels for filling and delivery, flow control means, acover, and an ullage which comprises a part of the base assembly.

Another prior art patent issued to one of the present applicants, namelyU.S. Pat. No. 5,743,879, discloses an injectable medicament dispenserfor use in controllably dispensing fluid medicaments such as insulin,anti-infectives, analgesics, oncolylotics, cardiac drugs,bio-pharmaceuticals, and the like from a pre-filled container at auniform rate. The dispenser, which is quite dissimilar in constructionand operation from that of the present invention, includes a storedenergy source in the form of a compressively deformable, polymeric,elastomeric member that provides the force necessary to controllablydischarge the medicament from a pre-filled container, which is housedwithin the body of the apparatus. After having been deformed, thepolymeric, elastomeric member will return to its starting configurationin a highly predictable manner.

BRIEF SUMMARY OF THE INVENTION

By way of brief summary, one form of the fluid delivery device of thepresent invention for dispensing medicaments to a patient comprises asupporting structure; a carriage assembly interconnected with thesupporting structure for movement between a first position and a secondposition; a pre-filled collapsible container carried by the carriageassembly, the collapsible container having accessing means for accessingthe reservoir comprising a frangible member in the form of a pierceablemember or shearable member. The apparatus also includes guide meansconnected to the supporting structure for guiding travel of the carriageassembly between the first position and said second positions; a storedenergy source operably associated with the carriage assembly for movingthe carriage assembly between the first and second positions; and anadministration set, including an administration line interconnected withthe outlet port of the collapsible reservoir. The stored energy sourceis cooperatively associated with the collapsible container of the deviceand functions to deliver a variable force to the container that tends tourge fluid flow therefrom at a substantially constant rate. In thepreferred form of the invention the stored energy source uniquelycomprises an elongated, pre-stressed strip of spring material that isformed into coils and exhibits a cross-sectional mass that varies alongits length.

Another object of the invention is to provide a compact fluid deliverydevice of the character described in the preceding paragraph in whichvariation in cross-sectional mass along the length of the retractablespring can be achieved by varying the width of the pre-stressed springalong its length.

Another object of the invention is to provide a compact fluid deliverydevice of the character described in which variation in cross-sectionalmass along the length of the retractable spring can be achieved byproviding spaced-apart apertures in the pre-stressed spring along itslength.

With the forgoing in mind, it is still another object of the presentinvention to provide a compact fluid delivery device for use incontrollably dispensing fluid medicaments to ambulatory patients, suchas, antibiotics, blood clotting agents, analgesics, KVO, artificialblood substitutes, resuscitation fluids, internal nutritional solutions,biologics, and like beneficial agents from pre-filled or field-filledcontainers at a uniform rate.

Another object of the invention is to provide a small, compactpre-filled fluid dispenser that is aseptically filled and sealed at thetime of manufacture.

Another object of the invention is to provide an apparatus that is ofsimple construction that can be used in the field with a minimum amountof training.

Another object of the invention is to provide a dispenser in which astored energy source is provided in the form of a highly novel variableforce retractable member of a unique construction that provides theforce necessary to continuously and uniformly expel fluid from theapparatus reservoir.

Another object of the invention is to provide a dispenser of the classdescribed which includes a fluid flow control assembly that preciselycontrols the flow of the medicament solution to the patient. Uniquely,the container is formed as a unitary structure that includes acollapsible side wall and a pierceable closure wall that isolates thebeneficial agents contained within the container reservoir from externalcontaminants.

Another object of the invention is to provide a dispenser that includesprecise variable flow rate selection.

Another object of the invention is to provide a fluid dispenser of theclass described which is compact, lightweight, is easy for ambulatorypatients to use, is fully disposable, transportable and is extremelyreliable in operation.

Another object of the invention is to provide a fluid dispenser asdescribed in the preceding paragraphs that is easy and inexpensive tomanufacture in large quantities.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a generally perspective, top view of one form of the fluiddelivery device of the present invention for dispensing medicaments to apatient.

FIG. 2 is a generally perspective, bottom view of the fluid deliverydevice shown in FIG. 1.

FIG. 3 is a generally perspective, exploded view of the fluid deliverydevice of the invention showing the top cover removed and theadministration set unfurled.

FIG. 4 is a foreshortened, longitudinal, cross-sectional view of thedevice showing the reservoir in a pre-filled condition.

FIG. 4A is a cross-sectional view taken along lines 4A-4A of FIG. 4.

FIG. 5 is a foreshortened, longitudinal, cross-sectional view, similarto FIG. 4, but showing the various components of the apparatus as theyappear following delivery to the patient of the fluid contained withinthe device reservoir with the reservoir substantially empty.

FIG. 6 is a top plan view of the collapsible container of thisembodiment of the invention.

FIG. 7 is a cross-sectional view taken along lines 7-7 of FIG. 6.

FIG. 8 is an exploded, cross-sectional view of the reservoir accessassembly of this form of the invention.

FIG. 9 is a view taken along lines 9-9 of FIG. 4.

FIG. 10 is a generally perspective view of a prior art retractablespring.

FIG. 11 is a generally perspective view of the prior art retractablespring shown in FIG. 10 as it appears in a partially expandedconfiguration.

FIG. 12 is a generally illustrative view of the configuration of aretractable spring that would deliver a force that decreases by a factorof w₁/w₂ as a spring returned from its fully extended configuration toits fully coiled configuration.

FIG. 13 is a generally graphical representation plotting pressure versusthe length of the reservoir container when a constant force spring isused to compress a bellows-like reservoir container.

FIG. 14 is a generally graphical representation, similar to FIG. 13,plotting pressure versus the degree of compression for the reservoircontainer when the container is compressed by a constant force spring.

FIG. 15 is a generally illustrative view of the retractable spring of afirst modified configuration.

FIG. 15A is a generally graphical representation plotting force exertedby the spring shown in FIG. 15 versus position along the length of thespring.

FIG. 16 is a generally illustrative view of the retractable spring of asecond modified configuration.

FIG. 16A is a generally graphical representation plotting force exertedby the spring shown in FIG. 16 versus position along the length of thespring.

FIG. 17 is a generally illustrative view of the retractable spring of athird modified configuration.

FIG. 17A is a generally graphical representation plotting force exertedby the spring shown in FIG. 17 versus position along the length of thespring.

FIG. 18 is a generally illustrative view of the retractable spring of afourth modified configuration.

FIG. 18A is a generally graphical representation plotting force exertedby the spring shown in FIG. 18 versus position along the length of thespring.

FIG. 19 is a generally illustrative view of the retractable spring of afifth modified configuration.

FIG. 19A is a generally graphical representation plotting force exertedby the spring shown in FIG. 19 versus position along the length of thespring.

FIG. 20 is a generally illustrative view of the retractable spring of asixth modified configuration.

FIG. 20A is a generally graphical representation plotting force exertedby the spring shown in FIG. 20 versus position along the length of thespring.

FIG. 21 is a generally illustrative view of the retractable spring of aseventh modified configuration.

FIG. 21A is a generally graphical representation plotting force exertedby the spring shown in FIG. 21 versus position along the length of thespring.

FIG. 22 is a generally illustrative view of the retractable spring of aneighth modified configuration.

FIG. 22A is a generally graphical representation plotting force exertedby the spring shown in FIG. 22 versus position along the length of thespring.

FIG. 23 is a generally illustrative view of the retractable spring of aninth modified configuration.

FIG. 23A is a generally graphical representation plotting force exertedby the spring shown in FIG. 23 versus position along the length of thespring.

FIG. 24 is a generally illustrative view of the retractable spring of atenth modified configuration.

FIG. 24A is a generally graphical representation plotting force exertedby the spring shown in FIG. 24 versus position along the length of thespring.

FIG. 25 is a generally illustrative view of the retractable spring of aneleventh modified configuration.

FIG. 25A is a generally graphical representation plotting force exertedby the spring shown in FIG. 25 versus position along the length of thespring.

FIG. 26 is a generally illustrative view of the retractable spring of atwelfth modified configuration.

FIG. 26A is a generally graphical representation plotting force exertedby the spring shown in FIG. 26 versus position along the length of thespring.

FIG. 27 is a generally illustrative view of the retractable spring of athirteenth modified configuration.

FIG. 27A is a generally graphical representation plotting force exertedby the spring shown in FIG. 27 versus position along the length of thespring.

FIG. 27B is a generally perspective view of still another form ofmodified spring of the invention that here comprises a modification ofthe thirteenth modified spring configuration shown in FIG. 27 of thedrawings.

FIG. 28 is a generally illustrative view of the retractable spring of afourteenth modified configuration.

FIG. 28A is a generally graphical representation plotting force exertedby the spring shown in FIG. 28 versus position along the length of thespring.

FIG. 29 is a generally illustrative view of the retractable spring of afifteenth modified configuration.

FIG. 29A is a generally graphical representation plotting force exertedby the spring shown in FIG. 29 versus position along the length of thespring.

FIG. 30 is a generally illustrative view of the retractable spring of asixteenth modified configuration.

FIG. 30A is a generally graphical representation plotting force exertedby the spring shown in FIG. 30 versus position along the length of thespring.

FIG. 31 is a generally illustrative view of the retractable spring of aseventeenth modified configuration.

FIG. 31A is a generally graphical representation plotting force exertedby the spring shown in FIG. 31 versus position along the length of thespring.

FIG. 32 is a generally illustrative view of the retractable spring of aeighteenth modified configuration.

FIG. 32A is a generally graphical representation plotting force exertedby the spring shown in FIG. 32 versus position along the length of thespring.

FIG. 33 is a generally perspective, exploded view of the upper portionof the fluid delivery device of the invention showing the constructionof one form of the rate control of assembly of the device.

FIG. 33A is an enlarged, cross-sectional view of the selector housing ofthe device that houses the device selector member for selecting the rateof fluid flow from the fluid reservoir.

FIG. 33B is a view taken along lines 33B-33B of FIG. 33A.

FIG. 33C is a greatly enlarged cross-sectional view of one form of theselector member of the fluid delivery device.

DETAILED DESCRIPTION OF THE INVENTION Definitions

As used herein, the following terms have the following meanings:

Constant Force Spring

Constant force springs are a special variety of extension spring. Theyare tightly coiled wound bands of pre-hardened spring steel or stainlesssteel strip with built-in curvature so that each turn of the strip wrapstightly on its inner neighbor. When the strip is extended (deflected),the inherent stress resists the loading force, the same as a commonextension spring, but at a nearly constant (zero) rate. Theconstant-force spring is well suited to long extensions with no loadbuild-up. In use, the spring is usually mounted with the internaldiameter (ID) tightly wrapped on a drum and the free end attached to theloading force. Considerable flexibility is possible with constant-forcesprings because the load capacity can be multiplied by using two or morestrips in tandem, or back-to-back. Constant force springs are availablein a wide variety of sizes.

Force Generating Region

The force generating region of the prior art constant force spring meansthe region of the spring in which the force is generated. Moreparticularly, it should be understood that it is the change in radius ofcurvature of the prior art constant force spring that is responsible forthe generation of the force produced by the spring. In fact, the radiusof curvature of the prior art constant for spring changes fromessentially infinity to a value equal to the radius of the spool onwhich the spring is wound.

Note that because the force generating region takes up some portion ofthe length of the spring it will tend to average any point-by-pointchanges in physical or structural properties of the spring.

It should also be kept in mind that this force generating region takesup some part of the total length of the spring, and that this forcegenerating region moves as the degree of extension of the springchanges.

Modified Constant Force Spring (Variable Force Spring)

The modified constant force spring or variable force spring of thepresent invention comprises a spring of highly novel configuration thatincludes an elongated, pre-stressed strip of spring material that may bemetal, a polymer, a plastic, or a composite material with built-incurvature so that, like the conventional constant force spring, eachturn of the strip wraps tightly on its inner neighbor. Uniquely, theelongated pre-stressed strip of spring material exhibits across-sectional mass that varies along said length. This variation incross-sectional mass along the length of the spring can be achieved invarious ways, as for example, by varying the width of the pre-stressedstrip along its length and by providing spaced-apart apertures in thepre-stressed strip along its length.

Mass of Material

The term “mass of material” when used herein in connection with themodified constant force spring of the invention means the mass ofmaterial in the “force generating region” as previously defined herein.More particularly, increasing the mass of material in the “forcegenerating region” will increase the force provided by the spring.Conversely, decreasing the mass of material in the “force generatingregion” will result in a reduction of the force generated by the spring.The mass in the active region can be changed by changing the thicknessof the spring, the width of the spring, the density of material of thespring, or any combination of these.

Unitary Container

A closed container formed from a single component.

Continuous/Uninterrupted Wall

A wall having no break in uniformity or continuity.

Hermetically Sealed Container

A container that is designed and intended to be secure against the entryof microorganisms and to maintain the safety and quality of its contentsafter pressurizing.

Biologic

A virus, therapeutic serum, toxin, antitoxin, vaccine, blood, bloodcomponent or derivative, allergenic product, or analogous productapplicable to the prevention, treatment or cure of diseases or injuriesof man.

Drug

As defined by the Food, Drug and Cosmetic Act, drugs are “articles(other than food) intended for the use in the diagnosis, cure,mitigation, treatment, or prevention of disease in man or other animals,or to affect the structure or any function.”

Drug Product

A finished dosage form (e.g. tablet, capsule, or solution) that containsthe active drug ingredient usually combined with inactive ingredients.

Artificial Blood Substitutes

Blood Substitutes are used to fill fluid volume and/or carry oxygen andother gases in the cardiovascular system. These include volume expandersfor inert products, and oxygen therapeutics for oxygen-carryingproducts.

Resuscitation Fluids

Infusion of hyperosmotic-hyperoncotic solutions such as hypertonicsaline dextran (HSD) as used for resuscitation of traumatic shock andperioperative volume support or as an adjunct to other conventionalisotonic crystalloid solutions. Where hypotension is caused bymyocardial depression, pathological vasodilatation and extravascation ofcirculating volume due to widespread capillary leak, a resuscitativeeffort is attempted to correct the absolute and relative hypovolemia byrefilling the vascular tree. Here resuscitation with a small volume ofhypertonic-hyperoncotic solution allows systemic and splanchnichemodynamic and oxygen transport recovery, without an increase inpulmonary artery pressure. Alternate types of normotonic, hyperoncotic,hypertonic, and hypertonic-hyperoncotic solutions can be used forsystemic hemodynamic recovery.

KVO

KVO—keeping-the-vein-open in an IV set up, a phrase that refers to theflow rate of a maintenance IV line established as a prophylactic access.

Nutritionals

Dietary supplemental enteral nutrition support feeding solutions usedfor nasoenteric application typically used in nasogastric, nasoduodenaland nasojejunal or intravenous routes of administration.

Beneficial Agent

The term beneficial agent can include any substance or compound that isbiologically active and includes any physiologically orpharmacologically active substance that produces a localized or systemiceffect in humans or animals and that can be delivered by the presentinvention to produce a beneficial and useful result.

Diluent

A liquid that dilutes, as in an inert solution used to dilute amedicament. An inert liquid carrier of a beneficial agent.

Device

An instrument, apparatus, implement, machine, contrivance, implant, invitro reagent, or other similar or related article, including anycomponent, part or accessory, which is intended for use in thediagnosis, cure, treatment or prevention of disease. A device does notachieve its intended purpose through chemical action in the body and isnot dependent upon being metabolized to achieve its purpose.

Reservoir

A receptacle or chamber for storing a fluid. A part of a machine,apparatus, where liquid is stored.

Liquid Container

A receptacle for holding a liquid. A fluid dispenser that is carried ortransported.

Collapsible

To cause to fold, break down, or fall down or inward or as in bent-overor doubled-up so that one part lies on another.

Collapsible Container

A dispensing apparatus in which one or more walls of the container aremade of a material which will deform (collapse) when pressure is appliedthereto; or a dispensing apparatus having a collapsible or telescopingwall structure.

Aseptic Processing

The term ‘aseptic processing’ as it is applied in the pharmaceuticalindustry refers to the assembly of sterilized components and product ina specialized clean environment.

Sterile Product

A sterile product is one that is free from all living organisms, whetherin a vegetative or spore state.

Blow-Fill-Seal Process

The concept of aseptic blow-fill-seal (BFS) is that a container isformed, filled, and sealed as a unitary container in a continuous mannerwithout human intervention in a sterile enclosed area inside a machine.The process is multi-stepped, pharmaceutical grade resin is extrudedinto a tube, which is then formed into a container. A mandrel isinserted into the newly formed container and filled. The container isthen sealed, all inside a sterile shrouded chamber. The product is thendischarged to a non-sterile area for packaging and distribution.

Integrally Formed

An article of one-piece construction, or several parts that are rigidlysecured together and is smoothly continuous in form and that any suchcomponents making up the part have been then rendered inseparable.

Frangible

An article, item or object that is capable of being ruptured or broken,but does not necessarily imply any inherent materials weakness. Amaterial object, under load that demonstrates a mechanical strain ratedeformation behavior, leading to disintegration.

Luer Lock Connector

A connector used to connect medical apparatus. Classically, the Luerconsists of a tapered barrel and a conical male part that fits into itwith or without a seal.

Referring to the drawings and particularly to FIGS. 1 through 3, oneform of the fluid dispensing apparatus of the present invention fordispensing medicaments to a patient is there shown and generallydesignated by the numeral 20. The dispensing apparatus here comprises asupporting structure 22, which includes a housing 24 having an upperportion 25 and a generally cylindrically shaped skirt portion 26.Supporting structure 22 can be constructed from metal, plastic or anysuitable material. Connected to portion 26 is a base segment 27, thedetails of construction of which will presently be described.

Disposed within skirt portion 26 is a carriage assembly 28, which ismovable between a first position shown in FIG. 4 and a second positionshown in FIG. 5. Carriage assembly 28 here comprises a carriage 30having a carriage flange 30 a to which the novel stored energy means ofthe present invention is operably interconnected. Carriage assembly 28is releasably locked in its first position by a novel locking means thecharacter of which will be described in the paragraphs which follow.

Carried by carriage assembly 28 is a reservoir defining assembly 34 thatdefines a fluid reservoir 35. As illustrated in FIGS. 4, 5,6 and 7,reservoir defining assembly 34 includes a top wall 34 a, a continuousbellows-like sidewall 34 b that is connected to top wall 34 a and abottom wall 34 c that is connected to side wall 34 b. Bellows-likesidewall 34 b is movable from the expanded, starting configuration shownin FIG. 4 to the collapsed configuration shown in FIG. 5. As illustratedin FIGS. 4 and 7, bottom wall 34 c includes a cup-shaped portion 34 d.

This important reservoir defining container also includes a neck portion34 e which is sealed at the time of manufacture by a thin closure wall39. Neck portion 34 e forms a part of the novel reservoir access meansof the invention the purpose of which will presently be described. Asshown in FIG. 5, when the bellows-like sidewall 34 b is collapsed, thecup-shaped portion 34 d is disposed in close proximity to the neckportion 34 e and substantially fills the upper portion of thecollapsible container. In this embodiment of the invention fluidreservoir 35 is accessible via a penetrating member 40 a that is carriedby the septum-penetrating assembly generally designated in FIG. 4 by thenumeral 40. Penetrating member 40 a is adapted to pierce closure wall 39as well as a pierceable membrane 42 which is positioned over closurewall 39 by means of a closure cap 44 which is affixed to the neckportion 34 c of the container assembly (see also FIGS. 7 and 8).

Closure wall 39 is integrally formed with neck portion 34 e by means ofa novel aseptic blow-fill-seal technique that is also used to formreservoir defining assembly 34. This aseptic blow-fill-seal techniquecomprises the continuous extrusion through an extruder head of a lengthof a parison in the form of a hollow tube between and through twoco-acting first or main mold halves. The method includes the step ofcutting off the parison below the extruder head and above the main moldhalves to create an opening which allows a blowing and filling nozzleassembly to be moved downwardly into the opening in the parison formolding and thereafter filling a molded container.

When the container portion of the container assembly is filled with thedesired amount of liquid, the blowing and filling nozzle assembly isretracted from the opening in the parison. A separate pair of co-actingsecond or upper sealing mold halves are then moved together around theexposed length of parison to form and seal the container upper portion.The finished container assembly, completely formed, filled, and sealedas a unitary structure is then conveyed out of the molding apparatus.Further information concerning aseptic blow-fill and blow-fill-sealtechniques is available from Rommelag of Waiblingen, Germany and isdiscussed in U.S. Letters Pat. No. RE 27,155 issued to Hansen. Becauseof the pertinence of this latter patent, U.S. Pat. No. RE 27,155 ishereby incorporated by reference as though fully set forth herein.

The basic unitary container and the hermetically sealed reservoirportion of the container are closed by the thin closure wall 39.Following closure of the container by the thin closure wall 39, thepiercable septum membrane 42 is then positioned over the closure walland the cap 44 is positioned over the piercable septum and secured toneck portion 34 e by any suitable means such as adhesive bonding orsonic welding. It is to be understood that septum 42 can also beconstructed as a slit or partially slit member. It is important to notethat closure wall 39 effectively prevents the medicament containedwithin the fluid reservoir from coming in contact with externalcontaminants.

To controllably move the carriage assembly 28 from its first position toits second position, novel stored energy means are provided. This novelstored energy means, which is operably associated with carriageassembly, is here provided in the form of three uniquely formed variableforce springs 48 (FIG. 9), the character of which will presently bedescribed.

As illustrated in FIGS. 4, 4A and 5 the carriage locking means includesa locking member 50 having a shank portion 50 a which extends through akeyhole-shaped opening 28 c provided in the carriage base 28 b (see FIG.4A). The carriage locking means also includes a finger-engaging,operating member 52 that is connected to shank portion 50 a. Operatingmember 52 functions to rotate locking member 50 from a transverselocking position to a release position in alignment with keyhole opening28 c formed in carriage base 28 b. As the operating member is rotatedfrom a locked position to a release position, the stored energy means,or springs 48 (FIGS. 4 and 9) will move the carriage from a positionshown in FIG. 4 into the position shown in FIG. 5 and in so doing willurge the fluid contained within reservoir 35 to flow toward penetratingmember 40, into passageway 40 b formed in the penetrating member andtoward the rate control means of the invention, the construction andoperation of which will presently be described.

Turning now to a consideration of the stored energy sources, or variableforce springs 48, which form an extremely important feature of thepresent invention, it is to be understood that the objective of manyprior art fluid and drug delivery systems is to deliver fluid at aconstant flow rate. One method for achieving a constant flow rate overtime involves ensuring that the pressure driving the fluid through thedevice is constant, i.e., the pressure inside the fluid reservoir of thedevice is constant. In the present invention achieving constant pressurein the bellows-like fluid reservoir 35 of the device is an accomplishedin a unique manner by modifying a typical constant force spring, such asa Negator spring “NS”. Negator springs, which are of the generalcharacter illustrated in FIGS. 10 and 11 of the drawings, are readilycommercially available from a number of sources including Stock DriveProducts/Sterling Instruments of new Hyde Park, N.Y.

The prior art Negator extension spring comprises a pre-stressed flatstrip “FS” of spring material that is formed into virtually constantradius coils around itself or on a drum “Z” having a radius R-1 (FIG.11). The area identified in FIG. 11 of the drawings as “FGR” designatesthe “active region” or “the force generating region” of the constant forspring. It should be understood that in this “active region” the radiusof curvature of the spring changes and it is this change in radius ofcurvature of the spring that is responsible for the generation of theforce. In fact, the radius of curvature changes from essentiallyinfinity to a value equal to the radius R-1 of the spool on which thespring is wound. As will be discussed in greater detail hereinafter,increasing the mass of material in this “force generating region” willincrease the force provided by the spring. Conversely, decreasing themass of material in the “force generating region” will result in areduction of the force generated by the spring. The mass in the activeregion can be changed by changing the thickness of the spring, the widthof the spring, the density of material of the spring, or any combinationof these. It should be further noted that because the force generatingregion takes up some portion of the length of the spring it will tend toaverage any point-by-point changes in physical or structural propertiesof the spring. The variable L shown in FIG. 11 of the drawings isdefined to be the distance from the force generating region to the endof the spring. When deflected, the spring material straightens as itleaves the drum (see FIG. 11). This straightened length of springactually stores the spring's energy through its tendency to assume itsnatural radius.

The force delivered by a typical prior art constant force spring, suchas the Negator extension spring depends on several structural andgeometric factors. Structural factors include material composition andheat treatment. Geometric factors include the thickness of the spring“T”, the change in radius of curvature of the spring as the spring isextended, and the width “W” of the spring.

Turning now to a consideration of the novel variable force springs ofthe present invention, these springs can be constructed from variousmaterials, such as metal, plastic, ceramic, composite and alloys, thatis, intermetallic phases, intermetallic compounds, solid solution,metal-semi metal solutions including but not limited to Al/Cu, Al/Mn,Al/Si, Al/Mg, Al/Mg/Si, Al/Zn, Pb/Sn/Sb, Sn/Sb/Cu, Al/Sb, Zn/Sb, In/Sb,Sb/Pb, Au/Cu, Ti/Al/Sn, Nb/Zr, Cr/Fe, non-ferrous alloys, Cu/Mn/Ni,Al/Ni/Co, Ni/Cu/Zn, Ni/Cr, Ni/Cu/Mn, Cu/Zn, Ni/Cu/Sn. These springscomprise a novel modification of the prior art constant force springs toprovide variable springs suitable for use in many diverse applications

With the foregoing in mind, if one wanted to produce a spring thatdelivered a force that increased by a factor of two as the springreturned from its fully extended conformation to its equilibrium, orfully coiled conformation, one would require that, as illustrated inFIG. 12 of the drawings, the width of the spring change by a factor oftwo along its length. In the example illustrated in FIG. 13, the forcewill decrease by a factor of w₁/w₂ as the spring changes from a fullyextended configuration to a fully retracted configuration.

With the forgoing in mind, one form of the modified spring of thepresent invention can be described algebraically as follows:

If x denotes the position of a point along a line that is parallel tothe longitudinal axis of the spring and w(x) denotes the width of thespring at that point then:w(x)=(constant)xThis describes the case wherein the width varies linearly with x as isshown in FIG. 12 of the drawings.

However, it is to be observed that the relationship between a positionalong the longitudinal axis of the spring and the width of the spring atthat position need not be linear as shown in FIG. 12. Further, the widthof the spring could be any arbitrary function of x. Thus:w(x)=f(x)where (x) denotes an arbitrary function of x.

Using this concept a spring can be designed that can be used tocontrollably compress a bellows type reservoir, such as reservoir 35,which when compressed by the modified spring exhibits a pressure vs.degree of compression curve of the character shown in FIG. 14. Statedanother way, it is apparent that the concept can be employed to design aspring that generates a pressure that is independent of the degree ofcompression of the bellows-type reservoir.

By way of example, suppose that the pressure vs. degree of compressioncurve for a bellows-like container when compressed by a constant forcespring is exemplified by the curve P(x) and the force of the constantforce spring is identified as “FCFS”. Further assume that the drop inpressure as the container is compressed is due to the force “BF(x)”,which is the force required to compress the container. Then the netforce producing the pressure in the container can then be written:F(x)=FCFS−BF(x)

Assume for simplicity that the area on which the force F acts isconstant and is represented by “A”. Then the pressure in the bottle is:P(x)=(FCFS−BF(x))/AThis equation describes, in functional form, the curve labeled P(x) inFIG. 14, and includes explicitly the contributions of the two forcesgenerating the pressure within the reservoir 35 of the bellows-likecontainer, that is the force due to the spring and the force due to thebellows-like container.

The foregoing analysis allows one to design a spring, the force of whichchanges in such a way that the sum of all forces generating the pressurein the container is independent of the degree of the compression of thecontainer, i.e., independent of the variable x. The force delivered bysuch a spring can be stated as:F _(ms)(x)=FCFS+AF(x)Where “FCFS” is the force delivered by the original constant forcespring and AF(x) is an additional force whose functional form is to bedetermined. Thus, the modified spring can be thought of as beingcomposed of two parts, one part delivers the force of the originalconstant force spring (a force independent of x) and the other deliversa force that depends on the variable x.

For this system the net force generating the pressure in the reservoirof the bellows-like container is stated as:FS(x)=F _(ms)(x)−BF(x)=FCFS+AF(x)−BF(x)Assuming that:AF(x)=BF(x) for all x.Then the total force compressing the container is:FS(x)=FCFS+AF(x)−AF(x)=FCFSwhich force is independent of the degree of compression of thecontainer, and wherein the pressure within the container is independentof the degree of compression of the container.P _(ms)(x)=(FCFS+AF(x)−AF(x))/A=FCFS/AWhere P_(ms)(x) denotes the pressure in the fluid reservoir when themodified spring of the invention is used.

In designing the modified spring of the present invention, theinformation contained in the pressure vs. displacement curve when thecontainer is compressed by a constant force spring can be used todetermine how the cross-sectional mass, in this case the width of thespring, must vary as a function of x in order that the pressure in thecontainer when compressed with the modified spring remains constant.

The force delivered by the spring being linearly dependent on the widthof the spring if all other things remain constant, thus:AF(x)=(constant)w(x)Substituting this into equation:P(x)=(FCFS−BF(x))/A, then:P(x)=(FCFS−AF(x))/A=(FCFS−constant)w(x))/AHowever, it is to be observed that FCFS/A−P(x) is just the differencebetween the two curves shown in FIG. 14, FCFS/A being the horizontalline. Thus, the modification to the width, denoted w(x), of the originalconstant force spring is proportional to the difference between the twocurves shown in FIG. 14. In other words, the shape of the change in thewidth of the spring as a function of x is similar to the differencebetween the two curves as a function of x. Furthermore, one can simply“read off” the shape of the curve w(x) from the pressure vs.displacement curve.

The broader utility of a variable force spring, whose width defines thespecific force, may be that the spring design can be appropriatelyconstructed to deliver a non-linear and highly variable force to meet aspecific requirement. In this way, a spring that has a width that simplydecreases as it is unrolled could be used. Alternatively, the springcould have an increasing width, followed by a width that decreases againduring its distention. The spring force provided is therefore highlytunable to meet a variety of applications and requirements, simply byconstructing a spring of specific width at the desired distension.Although a virtually infinite number of designs are possible, by way ofnon-limiting example, several differently configured springs areillustrated in FIGS. 15 through 30 of the drawings.

Referring to FIG. 15 of the drawings one form of variable force springhaving varying cross-sectional mass along its length is thereillustrated. In this instance, the varying cross-sectional mass isachieved by a constant force spring that has been modified to exhibitvarying width along its length. As shown in FIG. 15A, which is a plot ofForce versus “L”, where “L” is the distance from the force generatingregion of the spring to the end of the spring, the spring provides adecreasing force as it is retracted. Conversely, the spring depicted inFIG. 16 of the drawings, which also achieves varying cross-sectionalmass by a spring exhibiting varying width along its length, provides agreater force as it retracts (see FIG. 16A).

With regard to the spring depicted in FIG. 17, this spring achievesvarying cross-sectional mass by a constant force spring that has beenmodified to exhibit varying width along its length and also to exhibitat least one area of reduced width along its length. As illustrated inFIG. 17A of the drawings, as this spring rolls up from the extendedposition shown in FIG. 17, it will provide gradually less force,followed by a non-linear reduction in force at the area designated inFIG. 17 as 55, followed again by a non-linear increase in force, andfinally at the point at which it is almost completely retracted,exhibits a gradually decreasing force.

FIG. 18 is a generally illustrative view of the retractable spring of amodified configuration somewhat similar to that shown in FIG. 15 of thedrawings. In this latest spring configuration the varyingcross-sectional mass is once again achieved by a constant force springthat has been modified to exhibit varying width along its length. Asillustrated in FIG. 18A, which is a generally graphical representationplotting force exerted by the spring shown in FIG. 18 versus “L”, thespring provides a decreasing force as it is retracted.

FIG. 19 is a generally illustrative view of still another form ofretractable spring wherein the varying cross-sectional mass is achievedby a constant force spring that has been modified to exhibit varyingwidth along its length. More particularly, this latest form of themodified spring exhibits a tapered body portion 57. As illustrated inFIG. 19A, which is a generally graphical representation plotting forceexerted by the spring shown in FIG. 19 versus “L”, that is the distancefrom the force generating region of the spring to the end of thespring., the spring provides a decreasing force as it is retracted.

FIG. 20 is a generally illustrative view of the yet another form ofretractable spring wherein the varying cross-sectional mass is achievedby a constant force spring that has been modified to exhibit varyingwidth along its length. More particularly, this latest form of themodified spring exhibits a tapered body portion 59, which unlike thebody portion 57 of the spring shown in FIG. 19 tapers downwardly ratherthan upwardly. As illustrated in FIG. 20A, which is a generallygraphical representation plotting force exerted by the spring shown inFIG. 20 versus “L”, the spring provides a decreasing force as it isretracted.

With regard to the spring depicted in FIG. 21, this spring, which issomewhat similar to the spring configuration shown in FIG. 17 of thedrawings, achieves varying cross-sectional mass by a constant forcespring that has been modified to exhibit varying width along its lengthand also to exhibit a plurality of areas of reduced width along itslength. As illustrated in FIG. 21A of the drawings, as this spring rollsup from the extended position shown in FIG. 21, it will providegradually less force, followed by a non-linear reduction in force at thearea designated in FIG. 21 as 60, followed again by a non-linearincrease in force, followed by a non-linear reduction in force at thearea designated in FIG. 21 as 60 a and finally at the point at which itis almost completely retracted, once again exhibits a graduallydecreasing force.

Referring next to FIG. 22 of the drawings, the spring there depicted,which is somewhat similar to the spring configuration shown in FIG. 21of the drawings, achieves varying cross-sectional mass by a constantforce spring that has also been modified to exhibit varying width alongits length and also to exhibit a plurality of areas of reduced widthalong its length. However, as illustrated in FIG. 22A of the drawings,as this spring rolls up from the extended position shown in FIG. 22, itwill provide gradually increased force, followed by a non-lineardecrease in force at the area designated in FIG. 22 as 61, followedagain by a non-linear increase in force, followed by a non-lineardecrease in force at the area designated in FIG. 22 as 61 a and finallyat the point at which it is almost completely retracted, once againexhibits a gradually increasing force.

Turning next to FIG. 23 of the drawings, the spring there depicted isalso somewhat similar to the spring configuration shown in FIG. 21 ofthe drawings. However, the spring shown in FIG. 23 does not exhibit atapered body portion like that of the spring illustrated in FIG. 21.Rather, the spring achieves varying cross-sectional mass by a constantforce spring that has also been modified only to exhibit a plurality ofareas of reduced width along its length. As illustrated in FIG. 23A ofthe drawings, as this spring rolls up from the extended position shownin FIG. 23, it will provide a slightly decreased force, followed by anon-linear decrease in force at the area designated in FIG. 23 as 63,followed again by a non-linear increase in force, followed by anon-linear decrease in force at the area designated in FIG. 23 as 63 a,followed again by a non-linear increase in force, followed by anon-linear decrease in force at the area designated in FIG. 23 as 63 band finally at the point at which it is almost completely retracted,once again exhibits a gradually decreasing force.

Referring now to FIG. 24 of the drawings, the spring there depicted, isalso somewhat similar to the spring configuration shown in FIG. 21 ofthe drawings. However, the spring shown in FIG. 24 exhibits both anon-tapered body portion such as that of the spring shown in FIG. 23 andalso exhibits a tapered body portion like that of the spring illustratedin FIG. 21. In this instance, the spring achieves varyingcross-sectional mass by a constant force spring that has been modifiedto exhibit a reduced width along its length and has also been modifiedto exhibit a plurality of areas of reduced width along its length. Asillustrated in FIG. 24A of the drawings, as this spring rolls up fromthe extended position shown in FIG. 24, it will provide a generallylinear force, followed by a non-linear decrease in force at the areadesignated in FIG. 24 as 67, followed again by a non-linear increase inforce, followed by a generally linear force, followed by a non-lineardecrease in force at the area designated in FIG. 24 as 67 a, followedagain by a non-linear increase in force, followed by a non-lineardecrease in force at the area designated in FIG. 24 as 67 b and finallyat the point at which it is almost completely retracted, once againexhibits a generally linear force.

Referring next to FIG. 25 of the drawings, the spring there depictedachieves varying cross-sectional mass by a constant force spring thathas been modified to exhibit an increased width along its length and hasalso been modified to exhibit a plurality of areas of reduced widthalong its length. As illustrated in FIG. 25A of the drawings, as thisspring rolls up from the extended position shown in FIG. 25, it willprovide an increase in force, followed by a non-linear decrease in forceat the area designated in FIG. 24 as 68, followed again by a non-linearincrease in force, followed by a gradually increasing force, followed bya non-linear decrease in force at the area designated in FIG. 25 as 68a, followed by an increase in force and finally at the point at which itis almost completely retracted, once again exhibits a substantiallyincrease in force.

Turning next to FIG. 26 of the drawings, the spring there depicted issomewhat similar to the spring configuration shown in FIG. 23 of thedrawings and does not exhibit a tapered, central body portion like thatof the spring illustrated in FIG. 21. Rather, the spring achievesvarying cross-sectional mass by a constant force spring that has beenmodified in its central body portion to exhibit a plurality of areas ofreduced width along its length and uniquely exhibits an outwardlytapered end portion. As illustrated in FIG. 26A of the drawings, as thisspring rolls up from the extended position shown in FIG. 26, it willprovide an increase in force at the area designated in FIG. 26 as 69,followed by a decrease in force, followed by an increase in force at thearea designated in FIG. 26 as 69 a, followed again by a decrease inforce and finally at the point 69 c at which it is almost completelyretracted, will exhibit a gradually increasing force.

Referring to FIG. 27 of the drawings still another form of variableforce spring having varying cross-sectional mass along its length isthere illustrated. In this instance, the varying cross-sectional mass isachieved by a constant force spring wherein the force generating regionof the spring has been modified to include a plurality of spaced-apartapertures “AP” along its length. As shown in FIG. 27A, which is aschematic plot (not to scale) of force versus cross-sectional mass, thespring uniquely provides an increasing force in a stair step fashion asit is retracted. It is to be understood, that the apertures formed inthe pre-stressed strip of spring material can be located in any desiredconfiguration and can be both transversely and longitudinallyspaced-apart to provide the desired force as the spring is retracted.

FIG. 27B is a generally perspective view of still another form of theretractable spring of a modified configuration that is somewhat similarto that shown in FIG. 27 of the drawings. However, in this latest springconfiguration the spring comprises a novel laminate construction made upof a first laminate FL and a second interconnected laminate SL. Thevarying cross-sectional mass is once again achieved by providing aplurality of the elongated transversely and longitudinally spaced-apartapertures, or slits.

Turning next to FIG. 28, still in other form of variable force springhaving varying cross-sectional mass along its length is thereillustrated. In this instance, the varying cross-sectional mass is onceagain achieved by a constant force spring wherein the force generatingregion of the spring has been modified to include a plurality ofspaced-apart, generally circular shaped apertures “AP-4” along itslength. As shown in FIG. 28A, which is a plot of force versuscross-sectional mass, the spring uniquely provides a decrease in force,followed by an increase in force, followed again by a lengthy decreasein force, followed by an increase in force and then followed by anotherdecrease in force.

Referring to FIG. 29, still in other form of variable force springhaving varying cross-sectional mass along its length is thereillustrated. In this instance, the varying cross-sectional mass is onceagain achieved by a constant force spring wherein the force generatingregion of the spring has been modified to include a plurality ofspaced-apart, generally circular shaped apertures “AP-1”, “AP-2” and“AP-3” along its length. As shown in FIG. 29A, which is a plot of forceversus cross-sectional mass, the spring uniquely provides the desiredvariable decrease in force followed by the desired variable increase inforce as it is retracted.

Turning to FIG. 30, still in other form of variable force spring havingvarying cross-sectional mass along its length is there illustrated. Inthis instance, the varying cross-sectional mass is once again achievedby a constant force spring wherein the force generating region of thespring has been modified to include a plurality of spaced-apart,generally circular shaped apertures “AP-1”, “AP-2”, “AP-3” and “AP-4”along its length. As shown in FIG. 30A, which is a plot of force versuscross-sectional mass, the spring uniquely provides the desired variabledecrease in force as it is retracted.

Referring to FIG. 31, still in other form of variable force springhaving varying cross-sectional mass along its length is thereillustrated. In this instance, the varying cross-sectional mass is onceagain achieved by a constant force spring wherein the force generatingregion of the spring has been modified to include a plurality oftransversely and longitudinally spaced-apart, generally circular shapedapertures of increasing diameter in a direction away from the forcegenerating region. As shown in FIG. 31 A, which is a plot of forceversus cross-sectional mass, the spring uniquely provides the desiredvariable decrease in force as it is retracted.

Referring to FIG. 32, still in other form of variable force springhaving varying cross-sectional mass along its length is thereillustrated. In this instance, the varying cross-sectional mass is onceagain achieved by a constant force spring wherein the force generatingregion of the spring has been modified to include a plurality oftransversely and longitudinally spaced-apart, generally circular shapedapertures of decreasing diameter in a direction away from the forcegenerating region. As shown in FIG. 32 A, which is a plot of forceversus cross-sectional mass, the spring uniquely provides the desiredvariable increase in force as it is retracted.

Considering further the operation of the device of the invention, withthe apparatus in the configuration shown in FIG. 4, and with the fluidreservoir 35 filled with the medicament or diluent to be dispensed tothe patient, the dispensing operation can be commenced by removing thetop cover 77, which is snapped over a cover connector 77 a that isprovided on a connector member 79. With the cover removed as depicted inFIG. 5 of the drawings, the administration line 58 a of theadministration set 58 can be unwrapped from the guide sleeve 79 a thatextends from connector member 79 and about which it has been coiled (seeFIG. 4). Removal of the top cover 77 also exposes selector memberhousing 80 that houses the important selector member 82 of theinvention, the operation of which will presently be described.

To control the flow of medicinal fluid from reservoir 35 toward theadministration set 58 of the invention and then on to the patient, flowcontrol means are provided. This novel fluid flow control means,comprises two cooperating components, namely a rate control means forcontrolling the rate of fluid flow from the collapsible reservoir and anoperating means for controlling fluid flow between the collapsiblereservoir and the rate control means.

Considering first the operating means of the invention, it can be seenby referring to FIG. 4 of the drawings, selector member housing 80carries a tear strip 84 which retains the selector member housing 80 inits first position and comprises the part of the operating means of theinvention. When the tear strip is removed, a rotary force exerted onthreaded selector member housing 80 will controllably move the housingalong with the penetrating member 40 a, which also comprises a part ofthe operating means of the invention, along the threads 22 a ofsupporting structure 22 into the second penetrating position shown inFIG. 5. As the penetrating member moves into the second position, itwill pierce the membrane 42 as well as the closure wall 39 in the mannershown in FIG. 5. Piercing of the membrane and the closure wall opens afluid communication path from reservoir 35 to the rate control means ofthe invention via central fluid passageway 40 b formed in penetratingmember 40 a.

Once the carriage locking means of the invention, which also comprises apart of the operating means of the invention, has been manipulated inthe manner previously described to release the carriage 28, the carriagewill move upwardly due to the urging of the variable force springs 48and in so doing will collapse the container 34 in the manner shown inFIG. 5 of the drawings. As the container collapses, the fluid containedwithin reservoir 35 will flow outwardly of the reservoir through theoutlet 36, into the passageway 40 b of the piercing member 40 a, througha filter 83 which is carried by the septum-penetrating assembly 40 andthen onward toward the rate control assembly 84 of the rate of controlmeans of the invention.

Considering in greater detail the important rate control means of theinvention, this important means comprises a novel rate control assembly84 the construction of which is the best seen in FIG. 31 of thedrawings. Rate control assembly 84 here comprises a rate control plate86 that is provided with circuitous fluid channels 86 a, 86 b, 86 c, 86d, 86 e and 86 f, each of which is of a different geometry includingchannel length, depth, width and geometry. During the fluid deliverystep, as the fluid flows from reservoir 35 into the inlet 86 p of ratecontrol plate via the orifice 88 a of the rate control cover 88, each ofthe circuitous fluid channels will fill with the medicinal fluid to bedispensed to the patient. From the circuitous fluid channels, the fluidwill flow into outlet passageways 90 a, 90 b, 90 c, 90 d, 90 e, 90 f and90 p respectively formed in rate control cover 90. From these outletpassageways, the fluid flows into and fills circumferentiallyspaced-apart fluid passageways 94 a, 94 b, 94 c, 94 d, 94 e and 94 fformed in selector housing 80 (see also FIG. 16B).

As best seen by referring to FIGS. 33 and 33C, selector member 82 isprovided with an inlet passageway 96 and an outlet passageway 98 that isinterconnected with inlet passageway 96 by means of an axially extendingstub passageway 100 which, in turn, is connected to a circumferentiallyextending channel passageway 102 formed in selector member 82 (FIG.33C). With this construction, by rotating the selector member 82, inletpassageway 96 can be selectively brought into index with one of theradial extensions 104 of the axially extending passageways formed inselector member housing 82 thereby providing fluid communication betweenoutlet passageway 98 and the selected one of the circuitous flowpassageways formed in rate control plate 86 via annular channelpassageway 102 and the selected axially extending passageway formed inthe selector member housing 80. Since outlet passageway 98 is in fluidcommunication with the administration set 58 of the invention viapassageway 106 (FIG. 33A), the rate of fluid flow toward the patient canbe precisely controlled by selecting a rate control passageway ofappropriate configuration and length that is formed in rate controlplate 86.

More particularly, the desired flow rate can be selected by controllablyrotating the selector member 82, which is secured in position by aselector member retainer component 110, to the desired flow rateindicated by the indicia “I” that is imprinted on the selector memberretainer component 110 (see FIG. 33).

To recover any medicament that may remain in reservoir 35 following thefluid delivery step, a pierceable septum 113, which is carried byselector member 82, can be conveniently pierced using a conventionalsyringe, or like apparatus (not shown). Piercing of septum 113 openscommunication between reservoir 35 and the syringe via inlet 115 a of acentral passageway 115, via the rate control assembly 84, via passageway115 a and via passageway 40 b of penetrating member 40 a so that anyremaining medicament can be readily extracted from reservoir 35.

It is to be noted that the movable components of the dispensingapparatus typically carry conventional “O”-rings to provide appropriatesealing of the components within the apparatus with their mating parts.Throughout the drawings these “O”-rings are identified as “O”.

In the present form of the invention, administration set 58, whichcomprises a part of the dispensing means of the invention for deliveringmedicinal fluids to the patient, includes, in addition to administrationline 58 a, a conventional “Y”-site injection septum or port 58 b, aconventional gas vent and particulate filter 58 c and a line clamp 58 d.Provided at the distal end of the administration line is a Luerconnector 58 e of conventional construction (FIG. 3) which enables theapparatus to be interconnected with the patient in a conventionalmanner.

Having now described the invention in detail in accordance with therequirements of the patent statutes, those skilled in this art will haveno difficulty in making changes and modifications in the individualparts or their relative assembly in order to meet specific requirementsor conditions. Such changes and modifications may be made withoutdeparting from the scope and spirit of the invention, as set forth inthe following claims.

The invention claimed is:
 1. A fluid delivery device for dispensingmedicaments to a patient comprising: (a) a supporting structurecomprising a base assembly and a housing rotatably interconnected withsaid base assembly; (b) a carriage assembly carried by said baseassembly of said supporting structure for movement between a firstposition and a second position; (c) locking means carried by saidsupporting structure for locking said carriage assembly in said firstposition; (d) a unitary pre-filled collapsible container formed in acontinuous manner and carried by said carriage assembly, saidcollapsible container containing the medicaments to be dispensed to thepatient and having a continuous, uninterrupted wall formed of a singlematerial, said uninterrupted wall including a bellows-like sidewall, aneck portion connected to said bellows-like side wall, a top wallcontinuously formed with said bellows-like sidewall and a bottom wallcontinuously formed with said sidewall, said bottom wall including acup-shaped portion which, upon the collapse of said collapsiblecontainer is disposed in close proximity to said neck portion, saidbellows-like sidewall, said top wall and said bottom wall cooperating toform a hermetically sealed reservoir having an outlet port; (e) a storedenergy means operably associated with said carriage assembly for movingsaid carriage assembly between said first and second positions, saidstored energy means comprising a plurality of elongated, pre-stressedstrips of spring material having a first end and a second end, saidfirst end being interconnected with said carriage assembly; (f) anadministration set, including an administration line interconnected withsaid outlet port of said collapsible reservoir; and (g) fluid flowcontrol means carried by said base assembly of said supporting structurefor controlling fluid flow from said collapsible reservoir toward saidadministration set, said flow control means comprising rate controlmeans for controlling the rate of fluid flow from said collapsiblereservoir toward said administration set and further comprisingoperating means for controlling fluid flow between said collapsiblereservoir and said rate control means.
 2. The fluid delivery device asdefined in claim 1 in which said collapsible container further comprisesa neck portion integrally formed with said side wall, a pierceablemembrane superimposed over said neck portion and a closure cap affixedto said neck portion.
 3. The fluid delivery device as defined in claim 2in which said operating means comprises a penetrating member forpenetrating said pierceable membrane and said top wall of saidcollapsible container upon rotation of said housing relative to saidbase assembly.
 4. The fluid delivery device as defined in claim 2 inwhich said locking means for locking said carriage assembly in saidfirst position comprises a locking member rotatably connected to saidcarriage for movement relative to said carriage between a lockedposition and an unlocked position.